Spirometry: Measurement of volume of air inhaled or exhaled by the lung.Forced Expiratory Volume: Measure of the maximum amount of air that can be expelled in a given number of seconds during a FORCED VITAL CAPACITY determination . It is usually given as FEV followed by a subscript indicating the number of seconds over which the measurement is made, although it is sometimes given as a percentage of forced vital capacity.Vital Capacity: The volume of air that is exhaled by a maximal expiration following a maximal inspiration.Respiratory Function Tests: Measurement of the various processes involved in the act of respiration: inspiration, expiration, oxygen and carbon dioxide exchange, lung volume and compliance, etc.Pulmonary Disease, Chronic Obstructive: A disease of chronic diffuse irreversible airflow obstruction. Subcategories of COPD include CHRONIC BRONCHITIS and PULMONARY EMPHYSEMA.Asthma: A form of bronchial disorder with three distinct components: airway hyper-responsiveness (RESPIRATORY HYPERSENSITIVITY), airway INFLAMMATION, and intermittent AIRWAY OBSTRUCTION. It is characterized by spasmodic contraction of airway smooth muscle, WHEEZING, and dyspnea (DYSPNEA, PAROXYSMAL).Bronchodilator Agents: Agents that cause an increase in the expansion of a bronchus or bronchial tubes.Airway Obstruction: Any hindrance to the passage of air into and out of the lungs.Lung Diseases, Obstructive: Any disorder marked by obstruction of conducting airways of the lung. AIRWAY OBSTRUCTION may be acute, chronic, intermittent, or persistent.Lung Diseases: Pathological processes involving any part of the LUNG.Lung: Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.Maximal Midexpiratory Flow Rate: Measurement of rate of airflow over the middle half of a FORCED VITAL CAPACITY determination (from the 25 percent level to the 75 percent level). Common abbreviations are MMFR and FEF 25%-75%.Forced Expiratory Flow Rates: The rate of airflow measured during a FORCED VITAL CAPACITY determination.Dyspnea: Difficult or labored breathing.Peak Expiratory Flow Rate: Measurement of the maximum rate of airflow attained during a FORCED VITAL CAPACITY determination. Common abbreviations are PEFR and PFR.Pulmonary Medicine: A subspecialty of internal medicine concerned with the study of the RESPIRATORY SYSTEM. It is especially concerned with diagnosis and treatment of diseases and defects of the lungs and bronchial tree.Oscillometry: The measurement of frequency or oscillation changes.Airway Resistance: Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.Respiration Disorders: Diseases of the respiratory system in general or unspecified or for a specific respiratory disease not available.Respiratory Tract DiseasesBronchial Provocation Tests: Tests involving inhalation of allergens (nebulized or in dust form), nebulized pharmacologically active solutions (e.g., histamine, methacholine), or control solutions, followed by assessment of respiratory function. These tests are used in the diagnosis of asthma.Bronchospirometry: Spirometric technique in which the volume of air breathed in the right and left lung is recorded separately.Smoking: Inhaling and exhaling the smoke of burning TOBACCO.Maximal Expiratory Flow Rate: The airflow rate measured during the first liter expired after the first 200 ml have been exhausted during a FORCED VITAL CAPACITY determination. Common abbreviations are MEFR, FEF 200-1200, and FEF 0.2-1.2.Lung Volume Measurements: Measurement of the amount of air that the lungs may contain at various points in the respiratory cycle.Severity of Illness Index: Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.Exhalation: The act of BREATHING out.Plethysmography, Whole Body: Measurement of the volume of gas in the lungs, including that which is trapped in poorly communicating air spaces. It is of particular use in chronic obstructive pulmonary disease and emphysema. (Segen, Dictionary of Modern Medicine, 1992)Respiratory Therapy: Care of patients with deficiencies and abnormalities associated with the cardiopulmonary system. It includes the therapeutic use of medical gases and their administrative apparatus, environmental control systems, humidification, aerosols, ventilatory support, bronchopulmonary drainage and exercise, respiratory rehabilitation, assistance with cardiopulmonary resuscitation, and maintenance of natural, artificial, and mechanical airways.Pulmonary Diffusing Capacity: The amount of a gas taken up, by the pulmonary capillary blood from the alveolar gas, per minute per unit of average pressure of the gradient of the gas across the BLOOD-AIR BARRIER.Breathing Exercises: Therapeutic exercises aimed to deepen inspiration or expiration or even to alter the rate and rhythm of respiration.Respiratory Sounds: Noises, normal and abnormal, heard on auscultation over any part of the RESPIRATORY TRACT.Cross-Sectional Studies: Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.Occupational Exposure: The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.Albuterol: A short-acting beta-2 adrenergic agonist that is primarily used as a bronchodilator agent to treat ASTHMA. Albuterol is prepared as a racemic mixture of R(-) and S(+) stereoisomers. The stereospecific preparation of R(-) isomer of albuterol is referred to as levalbuterol.Methacholine Chloride: A quaternary ammonium parasympathomimetic agent with the muscarinic actions of ACETYLCHOLINE. It is hydrolyzed by ACETYLCHOLINESTERASE at a considerably slower rate than ACETYLCHOLINE and is more resistant to hydrolysis by nonspecific CHOLINESTERASES so that its actions are more prolonged. It is used as a parasympathomimetic bronchoconstrictor agent and as a diagnostic aid for bronchial asthma. (From Martindale, The Extra Pharmacopoeia, 30th ed, p1116)Cough: A sudden, audible expulsion of air from the lungs through a partially closed glottis, preceded by inhalation. It is a protective response that serves to clear the trachea, bronchi, and/or lungs of irritants and secretions, or to prevent aspiration of foreign materials into the lungs.Administration, Inhalation: The administration of drugs by the respiratory route. It includes insufflation into the respiratory tract.Occupational Diseases: Diseases caused by factors involved in one's employment.Primary Health Care: Care which provides integrated, accessible health care services by clinicians who are accountable for addressing a large majority of personal health care needs, developing a sustained partnership with patients, and practicing in the context of family and community. (JAMA 1995;273(3):192)Dust: Earth or other matter in fine, dry particles. (Random House Unabridged Dictionary, 2d ed)Breath Tests: Any tests done on exhaled air.Pulmonary Ventilation: The total volume of gas inspired or expired per unit of time, usually measured in liters per minute.Total Lung Capacity: The volume of air contained in the lungs at the end of a maximal inspiration. It is the equivalent to each of the following sums: VITAL CAPACITY plus RESIDUAL VOLUME; INSPIRATORY CAPACITY plus FUNCTIONAL RESIDUAL CAPACITY; TIDAL VOLUME plus INSPIRATORY RESERVE VOLUME plus functional residual capacity; or tidal volume plus inspiratory reserve volume plus EXPIRATORY RESERVE VOLUME plus residual volume.Residual Volume: The volume of air remaining in the LUNGS at the end of a maximal expiration. Common abbreviation is RV.Pulmonary Emphysema: Enlargement of air spaces distal to the TERMINAL BRONCHIOLES where gas-exchange normally takes place. This is usually due to destruction of the alveolar wall. Pulmonary emphysema can be classified by the location and distribution of the lesions.Maximal Expiratory Flow-Volume Curves: Curves depicting MAXIMAL EXPIRATORY FLOW RATE, in liters/second, versus lung inflation, in liters or percentage of lung capacity, during a FORCED VITAL CAPACITY determination. Common abbreviation is MEFV.Pulmonary Atelectasis: Absence of air in the entire or part of a lung, such as an incompletely inflated neonate lung or a collapsed adult lung. Pulmonary atelectasis can be caused by airway obstruction, lung compression, fibrotic contraction, or other factors.Respiratory Physiological Phenomena: Physiological processes and properties of the RESPIRATORY SYSTEM as a whole or of any of its parts.Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Bronchial Hyperreactivity: Tendency of the smooth muscle of the tracheobronchial tree to contract more intensely in response to a given stimulus than it does in the response seen in normal individuals. This condition is present in virtually all symptomatic patients with asthma. The most prominent manifestation of this smooth muscle contraction is a decrease in airway caliber that can be readily measured in the pulmonary function laboratory.Bronchoconstrictor Agents: Agents causing the narrowing of the lumen of a bronchus or bronchiole.Plethysmography: Recording of change in the size of a part as modified by the circulation in it.Reference Values: The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.Asthma, Occupational: Asthma attacks caused, triggered, or exacerbated by OCCUPATIONAL EXPOSURE.Respiratory Mechanics: The physical or mechanical action of the LUNGS; DIAPHRAGM; RIBS; and CHEST WALL during respiration. It includes airflow, lung volume, neural and reflex controls, mechanoreceptors, breathing patterns, etc.Respiratory Muscles: These include the muscles of the DIAPHRAGM and the INTERCOSTAL MUSCLES.Bronchitis: Inflammation of the large airways in the lung including any part of the BRONCHI, from the PRIMARY BRONCHI to the TERTIARY BRONCHI.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Skin Tests: Epicutaneous or intradermal application of a sensitizer for demonstration of either delayed or immediate hypersensitivity. Used in diagnosis of hypersensitivity or as a test for cellular immunity.Cystic Fibrosis: An autosomal recessive genetic disease of the EXOCRINE GLANDS. It is caused by mutations in the gene encoding the CYSTIC FIBROSIS TRANSMEMBRANE CONDUCTANCE REGULATOR expressed in several organs including the LUNG, the PANCREAS, the BILIARY SYSTEM, and the SWEAT GLANDS. Cystic fibrosis is characterized by epithelial secretory dysfunction associated with ductal obstruction resulting in AIRWAY OBSTRUCTION; chronic RESPIRATORY INFECTIONS; PANCREATIC INSUFFICIENCY; maldigestion; salt depletion; and HEAT PROSTRATION.Education, Nursing, Continuing: Educational programs designed to inform nurses of recent advances in their fields.Scopolamine Derivatives: Analogs or derivatives of scopolamine.Anti-Asthmatic Agents: Drugs that are used to treat asthma.Practice Guidelines as Topic: Directions or principles presenting current or future rules of policy for assisting health care practitioners in patient care decisions regarding diagnosis, therapy, or related clinical circumstances. The guidelines may be developed by government agencies at any level, institutions, professional societies, governing boards, or by the convening of expert panels. The guidelines form a basis for the evaluation of all aspects of health care and delivery.Bronchitis, Chronic: A subcategory of CHRONIC OBSTRUCTIVE PULMONARY DISEASE. The disease is characterized by hypersecretion of mucus accompanied by a chronic (more than 3 months in 2 consecutive years) productive cough. Infectious agents are a major cause of chronic bronchitis.Auscultation: Act of listening for sounds within the body.Air Pollutants, Occupational: Air pollutants found in the work area. They are usually produced by the specific nature of the occupation.Early Diagnosis: Methods to determine in patients the nature of a disease or disorder at its early stage of progression. Generally, early diagnosis improves PROGNOSIS and TREATMENT OUTCOME.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Sputum: Material coughed up from the lungs and expectorated via the mouth. It contains MUCUS, cellular debris, and microorganisms. It may also contain blood or pus.Physician's Practice Patterns: Patterns of practice related to diagnosis and treatment as especially influenced by cost of the service requested and provided.Respiratory Therapy Department, Hospital: Hospital department which is responsible for the administration of diagnostic pulmonary function tests and of procedures to restore optimum pulmonary ventilation.Inspiratory Capacity: The maximum volume of air that can be inspired after reaching the end of a normal, quiet expiration. It is the sum of the TIDAL VOLUME and the INSPIRATORY RESERVE VOLUME. Common abbreviation is IC.Deinstitutionalization: The practice of caring for individuals in the community, rather than in an institutional environment with resultant effects on the individual, the individual's family, the community, and the health care system.September 11 Terrorist Attacks: Terrorism on September 11, 2001 against targets in New York, the Pentagon in Virginia, and an aborted attack that ended in Pennsylvania.Diagnostic Errors: Incorrect diagnoses after clinical examination or technical diagnostic procedures.Rhinitis, Allergic, Perennial: Inflammation of the mucous membrane of the nose similar to that found in hay fever except that symptoms persist throughout the year. The causes are usually air-borne allergens, particularly dusts, feathers, molds, animal fur, etc.Tasmania: An island south of Australia and the smallest state of the Commonwealth. Its capital is Hobart. It was discovered and named Van Diemen's Island in 1642 by Abel Tasman, a Dutch navigator, in honor of the Dutch governor-general of the Dutch East Indian colonies. It was renamed for the discoverer in 1853. In 1803 it was taken over by Great Britain and was used as a penal colony. It was granted government in 1856 and federated as a state in 1901. (From Webster's New Geographical Dictionary, 1988, p1190 & Room, Brewer's Dictionary of Names, p535)Predictive Value of Tests: In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.Ipratropium: A muscarinic antagonist structurally related to ATROPINE but often considered safer and more effective for inhalation use. It is used for various bronchial disorders, in rhinitis, and as an antiarrhythmic.Bronchial DiseasesMaximal Voluntary Ventilation: Measure of the maximum amount of air that can be breathed in and blown out over a sustained interval such as 15 or 20 seconds. Common abbreviations are MVV and MBC.Exercise Test: Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.Bronchiectasis: Persistent abnormal dilatation of the bronchi.Adrenal Cortex HormonesWeldingIntermittent Positive-Pressure Breathing: Application of positive pressure to the inspiratory phase of spontaneous respiration.Emphysema: A pathological accumulation of air in tissues or organs.Functional Residual Capacity: The volume of air remaining in the LUNGS at the end of a normal, quiet expiration. It is the sum of the RESIDUAL VOLUME and the EXPIRATORY RESERVE VOLUME. Common abbreviation is FRC.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.